System and method of using location technology to aid patient recovery

ABSTRACT

A system for telemetrically monitoring a patient includes a remote monitoring device associated with the patient. A location services system tracks a location of the remote monitoring device. A patient tracking computer calculates a distance and a duration of patient ambulation from the tracked location. A method of monitoring an ambulatory patient monitors the location of a remote monitoring device and derives ambulatory event data from the monitored location.

BACKGROUND

The present disclosure is related to the field of telemetry. Moreparticularly, the present disclosure is related to systems and methodsof monitoring patient location in order to aid in patient recovery.

Patients recovering in telemetry wards or other hospital settings areoften encouraged to exercise, if possible, by walking. Currently, thisis merely encouraged or requested of the patient, but no specificdemands are made.

In some settings, a patient may be provided with a pedometer thatmeasures distance traveled by the patient over the course of a day, butthis information must be manually recorded by a clinician and there isno ability to differentiate types of patient movement.

BRIEF DISCLOSURE

A system for telemetrically monitoring a patient includes a remotemonitoring device associated with the patient. The remote monitoringdevice obtains a physiological value from the patient and broadcasts thephysiological value. A location services (LS) system tracks a locationof the remote monitoring device. A patient tracking computer iscommunicatively connected to the remote monitoring device and the LS.The patient tracking computer receives the physiological value and thelocation of the remote monitoring device and calculates a distance and aduration of a patient ambulation from the received locations.

An alternative embodiment of a system of monitoring an ambulatorypatient includes a remote monitoring device associated with theambulatory patient. A location services (LS) system tracks a position ofthe remote monitoring device. A patient tracking computer iscommunicatively connected to the LS system. The patient trackingcomputer receives the position of the remote monitoring device and thepatient tracking computer calculates a distance traveled and an elapsedduration of an ambulatory event from the received positions of theremote monitoring device.

A method of monitoring an ambulatory patient includes providing theambulatory patient with a remote monitoring device. A location of theremote monitoring device is tracked with a location services (LS)system. An ambulatory event is monitored with a patient trackingcomputer. The patient tracking computer is communicatively connected tothe remote monitoring device and the LS. Ambulatory event data isderived from the tracked location. The ambulatory event data includes anambulatory event distance and an ambulatory event time.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a floor plan with alternative ambulatory event routes anda plurality of telemetry receivers.

FIG. 2 is a schematic diagram depicting an embodiment of a telemetrysystem.

FIG. 3 is a schematic diagram depicting an alternative embodiment of atelemetry system.

FIG. 4 depicts an exemplary embodiment of a graphical user interfaceused in connection with embodiments of the system and method.

FIG. 5 is a flow chart depicting an embodiment of the method ofmonitoring an ambulatory patient.

FIG. 6 is a more detailed depiction of a portion of the floor plan ofFIG. 1 denoted by line 6-6 of FIG. 1.

DETAILED DISCLOSURE

FIG. 1 depicts a floor plan 10 of a telemetry ward or other clinicalsetting. The floor plan 10 includes a variety of exemplary landmarks onthe floor. These landmarks include a patient's room 12 and a nursingstation 14. Additionally, the floor plan 10 exemplarily includes aplurality of telemetry receivers 16 disposed throughout the floor plan10. Embodiments of the systems and methods incorporating one or more ofthese telemetry receivers 16 will be described in further detail herein.It is to be understood that alternative embodiments do not include aplurality of telemetry receivers 16, as will also be explained infurther detail herein.

The floor plan 10 further includes two alternative routes 18, 20 for anambulatory patient to travel. A short route 18 is represented by a solidline that connects the path A-B-F-G. A long route 20 is represented by adashed line and follows the path represented by A-B-C-D-E-F-G.

FIG. 2 is a schematic diagram of one possible arrangement for a locationservices (LS) system 22. This includes a remote monitoring device 24.The remote monitoring device 24 is associated with a particular patientwithin the telemetry ward. In an embodiment, the remote monitoringdevice 24 is a wireless electronic communication device that is worn orotherwise attached to the patient.

The remote monitoring device 24 broadcasts a location signal in radiofrequency (RF) that is indicative of the location of the remotemonitoring device 24 and the associated patient. The location signal maytake a variety of forms. Non-limiting examples of location signals mayinclude a beacon that is triangulated by beacon sensors, such astelemetry receivers 16. Alternatively, the remote monitoring device 24may include a global positioning system (GPS) technology such that theremote monitoring device 24 is able to determine a coordinate for itslocation. The location signal may then be a broadcast of this determinedlocation coordinate. In a still further embodiment, the remotemonitoring device may be a physiological monitoring device, as will bedescribed in greater detail herein with respect to an alternativeembodiment. In such an embodiment, the remote monitoring device 24 mayobtain and broadcast physiological data from the patient. The broadcastsignal with the physiological data may also be triangulated in order todetermine the location of the remote monitoring device 24.

The technology used by the monitoring device 24 to broadcast thelocation signal may be any of a variety of known broadcast technology.This includes the above-referenced radio frequency (RF) technology.Alternatively, the location signal may be broadcast in the form ofinfrared (IR) or ultrasound; however, these are not limiting on thetechnologies that may be used to broadcast the location signal.

As noted above, embodiments of the location services system 22 mayinclude a plurality of telemetry receivers 16 that receive the signalsbroadcast by the remote monitoring device 24. It is to be understoodthat the plurality of telemetry receivers 16 will be designed to receivethe type of signal broadcast by the remote monitoring device 24. Assuch, the telemetry receivers 16 may be receivers configured to receiveRF, IR, ultrasound, or other broadcast technology. It is to be furtherunderstood that the number and location of telemetry receiversdistributed throughout a telemetry ward may be dependent upon thebroadcast technology used. Therefore, in some embodiments a plurality oftelemetry receivers 16 may be distributed throughout the area, while inother embodiments only a single telemetry receiver may be necessary.

The telemetry receivers 16 are connected to an amplifier that amplifiesthe signal received by the telemetry receiver 16. Although not depicted,the amplifier 26 may also include other forms of signal conditioning orprocessing, including, but not limited to, filtering and/ordigitization.

Signals from the amplifier 26 are transmitted to a remote closet 28. Theremote closet 28 is connected to each of the plurality of telemetryreceivers 16 located in a defined area. In one example, the medical carefacility includes a telemetry ward that expands to multiple floors ofthe medical care facility. In such an example, a remote closet 28 may beplaced at each of the floors in order to collect and process the signalsreceived by the telemetry receivers 16 on that floor.

The remote closet 28 directs the received location signals from thetelemetry receiver 16 to an access point 30. The access point 30measures the strength of the location signals from the remote monitoringdevice 24 that are received by one or more telemetry receivers 16. Inthe location services system 22 wherein a plurality of telemetryreceivers 16 are distributed throughout the telemetry coverage area, thestrength of the location signals received at each of the telemetryreceivers 16 as determined by the access point 30 can be used totriangulate the remote monitoring device as the varying signal strengthfrom a plurality of telemetry receivers 16 may be used to determine thepatient location with reference to each of the telemetry receivers 16receiving the location signal.

The access point 30 of the remote closet 28 provides the locationinformation, including the received signal strengths, to a main closet32. The main closet 32 collects all of the information from theplurality of remote closets 28 distributed throughout the locationservices system 22. The access point 30 of the remote closet 28 providesthe location information, including the received signal strengths, tothe main closet 32 through any number of information transmissiontechnologies, including wired, wireless, or fiber optic technologies. Anaccess point (AP) controller 34 is connected to each of the accesspoints 30 when a plurality of remote closets 28 exist in the locationservices system 22. The AP controller 34 coordinates the transmissionand reception of the location information from the access points 30 ofeach of the remote closets 28.

The location information is provided from the AP controller 34 to alocation services (LS) computer 36. The LS computer includes computerreadable code stored on a computer readable medium 38 that embodiessoftware as detailed further herein for calculating location informationregarding a patient.

The LS computer 36 operates according to the computer readable codeembodied on the computer readable medium 38 such that the LS computer 36tracks the location of the remote monitoring device 24 based upon areceived location signal. The LS computer 36 may track the location ofthe remote monitoring device 24 as a plurality of locations in real-time(RI), or in near-real-time, as determined by the refresh rates of theaccess point 30 and AP controller 34. alternatively, the LS computer 36may track the location of the remote monitoring device 24 at anyalternative appropriate time interval as would be recognized by one ofordinary skill in the art. Therefore, some embodiments may refresh thetracked patient location every second, while alternative embodiments maydetermine location every minute; however, these are merely exemplary andare not intended to be limiting on this disclosure.

The tracked patient location of the remote monitoring device 24 istransmitted from the LS computer 36 of the main closet 32 to a patienttracking computer 40. The patient tracking computer 40 can be connectedto a computer readable medium 42 which contains computer readable codethat upon execution by the patient tracking computer 40, causes thepatient tracking computer 40 to carry out the processes and functions asdisclosed herein.

The patient tracking computer 40 receives the plurality of trackedpatient locations of the remote monitoring device 24 from the LScomputer 36 and calculates at least one of a variety of patientambulatory event data from the received plurality of tracked patientlocations. The ambulatory event data may include a total distancetraveled by the remote monitoring device 24.

In order to facilitate data processing, the tracking of the remotemonitoring device 24 location may be broken into one or more ambulatoryevents. Each ambulatory event would have a defined beginning and adefined end. Therefore, the patient tracking computer 40 may determine adistance traveled by the remote monitoring device 24 over the course ofan ambulatory event. Alternatively, the patient tracking computer 40 maycalculate a time duration of the ambulatory event. In still furtherembodiments, the patient tracking computer 40 may calculate an averageor an instantaneous speed of the patient during the ambulatory eventfrom the calculated distance and the calculated duration, as disclosedabove with respect to alternative embodiments.

The patient tracking computer 40 may calculate the ambulatory event datausing one or more algorithms stored on the computer readable medium 42.In an exemplary embodiment of the algorithms used to calculate theambulatory event data, the patient tracking computer may calculate thedistance traveled between track patient location as a straight linebetween the two locations. A more advanced algorithm may be used tocalculate the distance traveled as an average distance traveled bytracked patients between similar locations.

In a still further embodiment, which will be described in greater detailherein, and particularly with respect to FIG. 6, the algorithms used bythe patient tracking computer 42 to calculate the ambulatory event datamay calculate the distance traveled by the patient between two trackedpatient locations based upon a probability analysis of various patientpaths. Such probabilities may be developed over time by monitoringlocation information for various ambulatory patients. This patientlocation information may be analyzed using an advanced neural network(ANN) or Bayesian analysis to determine likely patient routes betweentwo tracked patient locations. These likely patient routes are then usedto derive the distance traveled by the patient between the two trackedpatient locations. The advanced neural network or Bayesian analysis ofhistorical patient location information may result in an algorithm thatconsists of probabilities or Gaussian distributions related to theactual path taken by a patient between two tracked patient locations.

The patient tracking computer 40 is communicatively connected to anelectronic medical record (EMR) 44 of the patient such that theambulatory event data may be stored as part of the patient's electronicmedical record 44. The recordation of the ambulatory event data in thepatient's EMR 44 allows for the ambulatory event data to be used as aphysiological parameter to be considered in the evaluation of thepatient's medical status. Furthermore, the ambulatory event datacalculated by the patient tracking computer 40 may be sent to agraphical display 46. The graphical display 46 presents the calculatedambulatory data to a clinician, the patient, or the patient's friends orfamily. As will be disclosed in further detail herein, the presentationof ambulatory data to non-medical personnel, such as the patient or thepatient's friends and family, may provide additional benefits inexpressing the patient's condition and/or progression towards recoveryin a non-technical format.

FIG. 3 depicts a schematic diagram of a telemetry system 50 thatincorporates the location services system 22 (depicted in FIG. 2). It isto be noted that like numerals between FIGS. 2 and 3 represent likeelements to which the description with respect to FIG. 2 applies.Therefore, only those new elements found in the telemetry system 50 willbe described in greater detail herein with respect to FIG. 3. Thetelemetry system 50 is an exemplary embodiment of a system wherein an RFsignal bearing physiological data from the remotely monitored patient istriangulated and used to identify the patient's location.

The remote monitoring device 52 of the telemetry system 50 furthermonitors at least one physiological value from the patient andbroadcasts the at least one physiological value exemplarily using RF,although other technologies such as IR or ultrasound may be potentiallyused. A non-limiting example of the types of physiological values thatmay be obtained by the remote monitoring device 52 includes heart rate,an electrocardiogram (ECG), non-invasive blood pressure (NIBP), andSpO₂. However, this list is merely exemplary and is not intended to belimiting on the scope of physiological values that may be obtained fromthe patient by the remote monitoring device 52.

The remote monitoring device 52 broadcasts the at least onephysiological value obtained from the patient. In such an embodiment thelocation of the remote monitoring device 52 may be derived from thebroadcast at least one physiological value. In an alternativeembodiment, the remote monitoring device 52 may also broadcast anindependent location signal, as described above with respect to FIG. 2.In one such embodiment, the telemetry signals are broadcast at a lowfrequency and the location signals are broadcast at a high frequency.This facilitates the separation of the broadcasted physiological valuesfrom the broadcasted location. In an alternative embodiment thetelemetry signals and the location signals are broadcast using twodifferent broadcast modalities. In one exemplary embodiment, thetelemetry signal is broadcast in RF while the location signal isbroadcast in IR.

The at least one physiological value is transmitted through thetelemetry receiver 16 and amplifier 26 to the remote closet 28. Amultiplexer 54 receives the broadcast physiological signal and thelocation information. In one embodiment, the multiplexer 54 separates alower frequency telemetry signal from a higher frequency location signaland directs the received signals to the appropriate components of thetelemetry system 50 for further processing. In an alternative embodimentseparate receivers are distributed to receive separate broadcasts oftelemetry and location signals.

From the multiplexer 54, the physiological values are provided to atelemetry remote hub 56 that prepares the physiological values fortransmission from the remote closet 28 to the main closet 32. Thetelemetry remote hub 56 may transmit the physiological values to atelemetry base unit 58 in the main closet 32. The telemetry base unit 58receives and processes the physiological values. In an embodiment, thetransmission of the physiological values from the telemetry remote hub56 to the telemetry base unit 58 is performed by fiber optictransmission technology and the telemetry remote hub 56 and thetelemetry base unit 58 perform the signal conditioning required for theoptical fiber conversion necessary for the transmission.

After the physiological values are transmitted from the telemetry remotehub 56 to the telemetry base unit 58, the telemetry base unit 58processes the fiber optic signal to extract the physiological valuesembedded thereon. The telemetry base unit 58 sends the physiologicalvalues to a telemetry receiver 60 that receives physiological values andfurther directs the physiological values to a telemetry server (ATS) 62.The ATS 62 performs further analysis of the received physiologicalvalues, such as to process the received physiological values intoappropriate forms for storage and interpretation. Additionally, if thetelemetry system 50 is part of a broader system for telemetricallymonitoring the physiological condition of a patient, the ATS 62 mayderive additional physiological data from the received physiologicalvalues and/or apply institutional diagnostic rules such as to performautomatic or automated diagnostic tests or other patient monitoring.

The ATS 62 also receives the broadcast locations of the patient from theLS computer 36. The ATS 62 may coordinate the physiological values andthe locations from the patient with other patient, facility, or servicesinformation that may be necessary for the operation of other features ofthe telemetry system 50 that are not central to the present disclosure.Such additional telemetry systems functionalities include patientmedical history and EMR access, clinical staff information, medical carefacility availability, and facility capacity.

The ATS 62 transmits all of the physiological values and the patientlocations to the patient tracking computer 40. In addition to theambulatory event data calculated by the patient tracking computer 40 asdisclosed with respect to FIG. 2, when the patient tracking computer 40further receives physiological values from the ATS 62, the patienttracking computer may further calculate a correlation or otherrelationship between the at least one physiological value and theambulatory event data. Merely exemplary embodiments of such correlationsmay include a comparison of ambulatory event duration to patient heartrate, S_(p)O₂, or blood pressure. Alternative comparisons may similarlybe drawn between the ambulatory event distance and the physiologicalvalues noted above.

In still further embodiments, because the distance, duration, and/orspeed of the ambulatory event is known, this ambulatory event data maybe compared to a physiological value such as a measurement of thepatient's ECG. In this embodiment, the ambulatory event monitored by thetelemetry system 50 can be analyzed as a form of stress test whereinchanges to ECG morphology may be monitored with respect to an ongoingphysical stress to the patient. The types of morphological analysesperformed on ECG data are known to persons of ordinary skill in the artof stress tests. It is understood that while ECG has exemplarily beenidentified as the physiological value evaluated in the stress test,alternative physiological values may also be used in this analysis.

The patient tracking computer 40 is connected to the patient'selectronic medical record (EMR) 44 such that the results of thesecorrelative analysis may be recorded as part of the patient's electronicfile. Similarly, the results of these comparison between ambulatoryevent data and physiological values may be sent to a graphical display46 for presentation to clinicians, the patient, or others.

FIG. 6 is a more detailed depiction of an embodiment of a portion of thefloor plan of FIG. 1 denoted by line 6-6. FIG. 6 will herein be used todescribe additional features of embodiments of the system and method formonitoring an ambulatory event. More specifically, the floor plan ofFIG. 6 depicts an embodiment wherein the patient location is onlyintermittently determined or broadcast by the remote monitoring device.

In FIG. 6, a plurality of position beacons 92 A-K denote the actualposition of the patient as determined by the location services system.These beacons 92 A-K exemplarily represent constant time intervals. As amerely exemplarily embodiment, the location services system determinesactual patient location identified by the beacons 92 A-K once everyminute; however, it is understood that the intervals between the beacons92 A-K may be more or less including intervals that approach or achievereal-time or near-real-time.

Returning to the exemplary embodiment of FIG. 6, the patient completesthe short route 18 while on the path of A-B-F-G-A over the course ofapproximately 11 minutes, as represented by the eleven beacons 92 A-K.

When the patient location is only intermittently derived, algorithmsmust be implemented in order to sufficiently track the ambulatory event,and accurately monitor the distance traveled by the patient during theambulatory event.

As mentioned above, the algorithms used to calculate the distancetraveled by the patient during the ambulatory event may range incomplexity from a simple straight line path between position beacons toa more detailed analysis that incorporates information regarding thelikelihood of a patient to travel along a particular path between twoposition beacons. These algorithms may be derived through an analysis ofhistorical patient movements across a large number of patients on thesame ambulatory route or in the same ambulatory ward. Additionally, thealgorithms may be nuanced or particularized to specific patients aftersufficient ambulatory information for a particular patent is acquired.This historical patient location information may be used to identifypercentages or likelihoods that a patient will take a particular path(with a defined distance) between two position beacons. The algorithmsused to calculate the distance traveled between two position beacons maybe derived using a form of analysis such as an advanced neural networkor Bayesian analysis. As noted above, the results of this analysis ofhistorical patient location information may be probability or Gaussiandistributions related to particular patient paths between positionbeacon.

Information regarding the likelihood of patients to choose particularpaths and/or destinations may be incorporated into both the tracking ofpatient location during the ambulatory event and the calculation of thedistance traveled during the ambulatory event. For example, a room 94,such as a bathroom, may exist between beacons 92B and 92C. Due to theinterval between these two beacons, it may be that the distance traveledby the patient may be accurately represented by a straight line betweenbeacons 92B and 92C. Alternatively, the patient's path may be morecorrectly represented by line 95 that quickly enters the bathroom 94 andexits the bathroom 94 before the patient's location is determined again.

The above-noted analysis of historical patient location information mayidentify that it is very unlikely that the patient would enter a room,such as bathroom 94, for only a few seconds, such that a location beaconwould not appear in the bathroom 94. Exemplarily, the algorithm mayidentify that there is a 10% chance that the patient traveled path 95while there is a 75% chance that the patient traveled directly between92B and 92C. Thus, in such a situation, it may be accurately reflectedthat the patient most likely proceeded directly between beacon 92B and92C during the ambulatory event. A travel distance calculated by thealgorithm may be adjusted to account for these percentages, eitherselecting the distance of the most likely path or by providing aweighted average of the alternative path distances weighted by theirlikelihood percentages. These models or estimates may be adjusted basedupon the patient's average speed or instantaneous speed at the previousbeacon (92B). This additional ambulatory event data can promote moreaccurate tracking of patient ambulation paths and distances.

Another consideration is the specific layout of the short ambulatoryroute 18 itself. While a direct positional measurement between beacons92C and 92D would represent the shortest distance between these twoadjacent beacons, information regarding the ambulatory route itself maybe programmed such that it is known by the system that a direct path 96,such as between beacon 92C and 92D or 92D and 92E, is not possible dueto the physical constraints of the hallway of the short route 18 itself.In such an instance, an algorithm executed by the patient trackingcomputer may assign a probability of 0% to a direct path between beacons92C and 92D, or any other possible path that intersects the wall of thehallway. Thus, the ambulation distance respectively between beacons 92Cand 92D or 92D and 92E must compensate for the corner of the hallwaysthat must be traversed by the patient. As with the example above, afavored or most probable path between 92C and 92D (and an associateddistance) may be identified through the analysis of historical patientlocation information.

A still further example of intermittent beacon interpretation isrepresented by group 98 of beacons 92F, 92G, and 92H. Since each of thebeacons in group 98 are within close proximity to one another, thelocation services system may interpret this group 98 in a variety ofways. In one embodiment, the location services system may interpret thatthe patient has moved great distances between consecutive beacons,however, was in roughly the same position each time that these beaconswere obtained. Alternatively, the location services system may interpretthat the patient has remained generally still and thus little totaldistance was traversed during this time interval. As with theinterpretation regarding the bathroom 94, compiled ambulatory data froma plurality of historical patients traversing the short ambulatory route18 may be used to provide statistical guidance with respect to theproper interpretation of beacon group 98.

It is unlikely that a slowly moving patient would quickly coverdistances back and forth while beacons are obtained at roughly the sameposition. Therefore, an exemplary patient location algorithm may assigna low probability of 5% to that analysis. Alternatively, the analysis ofhistorical patient location information may identify that such a group98 or pattern of position beacons likely (80%) can be interpreted thatthe patient paused during the ambulatory event, for example to conversewith another patient or a caregiver. In this exemplary embodiment thelocation services system may assume that beacon group 98 is a result ofthe patient stopping, and process the beacon group 98 by removing thetwo “unused” intervals (namely 92F-92G and 92G-92H) from the ambulatoryevent and simply interpret the event as though the patient moved frombeacon 92E to beacon 92F and then to beacon 921. Alternative embodimentsof the location services system may include a most probable path thatincorporates all of the beacons of beacon group 98. This would have theeffect of increasing the calculated time required by the patient tocomplete the ambulatory event while minimally increasing the distancecovered. These adjustments would result in a lowered calculated averagespeed over the course of the ambulatory event.

FIG. 4 depicts an embodiment of a graphical user interface (GUI) 64 thatmay be presented on the graphical display 46 (FIGS. 2 and 3). The GUI 64depicts exemplary embodiments of the ambulatory event data that may bepresented on the graphical display 46. The merely exemplary GUI 64 isdivided into four regions that each generally represent a different typeof ambulatory event data that may be presented on the GUI 64. It is tobe understood that alternative embodiments of the GUI 64 may includemore or fewer of these types of ambulatory event data.

Region 66 identifies information regarding the current day's(exemplarily Day 5) ambulatory event. This includes reporting a distance68 traveled by the patient during the ambulatory event. A time 70 isreported for the patient to complete the prescribed ambulatory event.Finally, an average speed 72 is calculated from the distance 68 and time70 and reported in region 66.

Region 74 presents a graph 76 depicting a comparison between aphysiological value and ambulatory event data from the Day 5 ambulatoryevent. The chart depicts the change in a patient's heart rate over thecourse of this single ambulatory event. The progress of the ambulatoryevent may be represented in terms of distance (feet) as in graph 76.Alternatively, the ambulatory event progress may be represented in termsof event duration (time). As represented in the graph 76, over thecourse of the ambulatory event the patient's heart rate increases fromapproximately 60 beats per minute to approximately 120 beats per minute.However, the graph 76 also shows that this increase is step-wise withplateaus rather than a steady increase. This graphical representation ofthe change in the patient's heart rate may provide assistance inevaluating patient condition as the patient's physiological response inthe form of heart rate is correlated to the stress of the prescribedambulatory event.

Region 78 presents a historical representation of a series of dailyambulatory events. This graphic may be obtained from information in thepatient's EMR. Region 78 includes a chart 80 that reports the varyingdistances and times for each daily ambulatory event of the patient.Looking at the distance graph 82, it can be seen that the ambulatoryevent distance increased from 20 feet to 50 feet between Day 3 and Day4. By reviewing the distance graph 82 with the context provided by thetime graph 84, it can be readily identified that the patient's time tocomplete the prescribed 20 foot ambulatory event steadily decreases from15 minutes to 7 minutes. After the patient completed the 20 footambulatory event on Day 3 in 7 minutes, the distance for the ambulatoryevent in Day 4 was increased to 50 feet. While the specific distancesand times used in the present description are merely exemplary, thisexample shows how an improvement in patient performance in a prescribedambulatory event over time can result in adjusting the ambulatory eventin order to continue the patient's recovery process. This recoveryprocess can also be noted in the decrease in time for the patient tocomplete the 50 foot ambulatory event between Day 4 and Day 5.

The graphical depiction of historical ambulatory event data as presentedin chart 80 can be a useful tool for presenting patient condition andrecovery to patients, or their family and friends who do not havemedical training. By relating patient recovery and improvement to a realworld task, such as an ambulatory event (walking a defined distance),patients and others presented with this data, may have a betterunderstanding of their physiological condition. The graphicalpresentation of the ambulatory event data can provide a goal or othermotivation in order to improve. Such improvement is visually seen andreinforced with each decrease in time for the completion of anambulatory event. The patient is rewarded and challenged due to theirimprovements by increasing the distance of the next ambulatory event.

Region 86 presents a prescribed ambulatory event for the next day (Day6). Since the patient reduced the time needed to complete the 50 footambulatory event between Day 4 and Day 5, the prescribed ambulatoryevent for Day 6, presented in region 86, is established at a distance 88of 100 feet. The prescribed completion time 90 for this ambulatory eventis set at 25 minutes. This presents the patient with a new ambulatorygoal, thus motivating the patient to continue progress towards recovery.

The GUI 64, presented in FIG. 4, thus provides a patient without medicaltraining a visual report that shows current ambulatory performance inrelation to physiological parameters and previous ambulatory eventperformance. This presentation of monitored physiological parameters incontext with a real-world activity can facilitate an understanding ofcurrent medical status by the patient and motivate the patient toimprove in ambulatory performance, aiding in recovery. The patient isfurther positively challenged by a prescribed ambulatory event that isbased upon the patient's previous ambulatory event performance.

Relating FIG. 1 to FIG. 4, the short route 18 and the long route 20depicted on the floor plan 10 of the telemetry ward, may relate toactual predetermined ambulatory event routes. In an exemplaryembodiment, the short route 18 may represent a prescribed ambulatoryevent of a distance of 20 feet. Thus, when the patient is prescribed a20 foot ambulatory event, the patient is instructed to follow the routeA-B-F-G. In some telemetry wards, this may be represented by a physicalline drawn with a specified color on the floor of the halls of thetelemetry ward. Continuing with this example, the long route 20 may berepresentative of an ambulatory event distance of 50 feet. Therefore,when prescribed with a 50 foot ambulatory event, the patient will followthe route A-B-C-D-E-F-G. For longer ambulatory events, the patient maycombine routes or make multiple laps of defined routes. Therefore, forthe prescribed Day 6 ambulatory event distance of 100 feet, the patientmay be instructed to follow the long route 20 for two laps beforecompletion. In another example, a 70 foot ambulatory event may beprescribed by completing one lap of the short route 18 and one lap ofthe long route 20; however, these are intended to be merely exemplary ofprescribed ambulatory event routes.

FIG. 5 is a flow chart depicting an embodiment of a method of monitoringan ambulatory patient 100. The method 100 begins with providing theambulatory patient with a remote monitoring device 102. As noted above,the remote monitoring device may be a wireless device that is attachedto, located on, or associated with the patient. The remote monitoringdevice may be specifically designed to track patient location; however,alternative embodiments of the remote monitoring device may also monitorphysiological parameters from the patient. Such physiological parametersmay include, but are not limited to, heart rate, NIBP, ECG, and SpO₂.

At 104, the location of the remote monitoring device is tracked. Asnoted above, the tracking of the remote monitoring device location maybe performed in a variety of manners by a location services system. Thelocation services system may be based upon GPS coordinates that aretransmitted from the remote monitoring device. Alternatively, the localservices system may track a radio frequency (RF) or infrared (IR) signalfrom the remote monitoring device that is indicative of the location ofthe remote monitoring device. In some embodiments, the RF or IR signalmay be triangulated by the location services system to track the devicelocation. Additionally, the location services system may be a real-timelocation services (RTLS) system.

In an optional embodiment, a patient pathway may be tracked at 106 bythe LS system. By concatenating a series of tracked device locationsfrom 104 over time, a pathway of the patient during an ambulatory eventmay be mapped. The mapping of the patient pathway at 106 may beperformed using a probability analysis as disclosed above usinghistorical patient location information to provide a likelihood, whichmay be a percentage, that the patient took a particular path betweendetected location beacons. The mapped pathway may be stored for laterreference, such as in the development of more detailed algorithms tointerpret patient movement between location beacons. Alternatively, themapped pathway may be presented on a graphical display to the patient ora clinician.

At 108, the ambulatory event is monitored with a patient trackingcomputer. The patient tracking computer receives the tracked location ofthe remote monitoring device from the LS system and monitors the devicelocation over the course of the ambulatory event. The patient trackingcomputer may apply one or more algorithms derived from historicalpatient location information to calculate a distance traveled betweenlocation beacons over the course of the ambulatory event. In someembodiments, monitoring the ambulatory event includes determining astart of an ambulatory event and an end of an ambulatory event andmonitoring the device location during the ambulatory event.

Next, at 110, the patient tracking computer derives ambulatory eventdata from the tracked locations across the ambulatory event. As notedabove, the ambulatory event data may include a variety of data,including: a distance traveled during the ambulatory event, a durationof the ambulatory event, and an average speed across the ambulatoryevent; however, these are not intended to be limiting on the types ofambulatory event data that may be derived by the patient trackingcomputer at 110.

At 112, the ambulatory event data derived at 110 is presented to apatient or clinician. The presentation of the ambulatory event data at112 may be performed by a graphical display and may be presented in theform of a GUI or may alternatively be presented to the patient orclinician in a textual format as sent in e-mail or SMS communications.

In an alternative embodiment, while the remote monitoring devicelocation is tracked at 104, the remote monitoring device is alsomeasuring a physiological value from the patient at 114. The remotemonitoring device transmits the measured physiological value to thepatient tracking computer. In one embodiment, the LS system uses thetransmission signal of the transmitted physiological value from theremote monitoring device in order to triangulate and track the remotemonitoring device location at 104.

After the physiological value has been measured and transmitted to thepatient tracking computer, the patient tracking computer at 116 presentsthe ambulatory event data and the physiological value in a comparativeformat. As noted above with respect to 112, the presentation of theambulatory event data and the physiological value in a comparativeformat may be performed by a graphical display using a GUI or textualbased communication.

As noted above, the comparative presentation of ambulatory event dataand physiological values may relate a change in physiological value overthe progress or course of the ambulatory event. In one non-limitingexample, at 116, the patient is presented with a plurality of SpO₂values measured during the course of an ambulatory event. The SpO₂values are presented in relation to the progress of the patient in theambulatory event such as determined by distance traveled or ambulatoryevent duration.

This written description uses examples to disclose the invention,including the best mode, and also to enable any person skilled in theart to make and use the invention. The patentable scope of the inventionis defined by the claims, and may include other examples that occur tothose skilled in the art. Such other examples are intended to be withinthe scope of the claims if they have structural elements that do notdiffer from the literal language of the claims, or if they includeequivalent structural elements with insubstantial differences from theliteral languages of the claims.

We claim:
 1. A system for telemetrically monitoring a patient, thesystem comprising: a remote monitoring device associated with thepatient, the remote monitoring device obtains a physiological value fromthe patient and broadcasts the physiological value; a location services(LS) system that tracks a plurality of locations of the remotemonitoring device; and a patient tracking computer communicativelyconnected to the remote monitoring device and the LS system, the patienttracking computer receives the physiological value and the plurality oflocations of the remote monitoring device and executes computer readablecode embodying an algorithm to calculate a distance traveled by thepatient and a duration of patient ambulation to travel the calculateddistance from the tracked plurality of locations received from the LSsystem, wherein the patient tracking computer applies an algorithm thatidentifies a plurality of possible paths between a first location of theplurality of locations of the remote monitoring device and a secondlocation of the remote monitoring device, and calculates a probabilitythat the remote monitoring device traveled a possible path associatedwith each of the plurality of possible paths, to calculate the distancetraveled by the patient.
 2. The system of claim 1, further comprising aglobal positioning system (GPS) within the remote monitoring device,wherein the GPS determines the plurality of locations of the remotemonitoring device and the remote monitoring device broadcasts each ofthe plurality of locations determined by the GPS to the LS system. 3.The system of claim 1, further comprising at least two telemetryreceivers that receive the physiological value broadcast by the remotemonitoring device, wherein the LS system determines the plurality oflocations of the remote monitoring device by triangulating the broadcastphysiological value.
 4. The system of claim 1, wherein the patienttracking computer further executes computer readable code that causesthe patient tracking computer to monitor an ambulatory event prescribedby a clinician, the ambulatory event being defined in the computerreadable code by a predetermined distance and a predetermined duration.5. The system of claim 4, wherein the patient tracking computer furthermonitors an elapsed time for the ambulatory event.
 6. The system ofclaim 5, further comprising a graphical display communicativelyconnected to the patient tracking computer, the graphical displaypresents the physiological value, the distance of the ambulatory event,and the elapsed time of the ambulatory event.
 7. The system of claim 4,wherein the patient tracking computer executes computer readable codesuch that the computer identifies the ambulatory event within theplurality of locations of the remote monitoring device received by thepatient tracking computer.
 8. The system of claim 7, wherein the patienttracking computer executes computer readable code such that thecalculated distance and calculated duration are a calculated distance ofthe ambulatory event and a calculated duration of the ambulatory event.9. The system of claim 8, further comprising a graphical displaycommunicatively connected to the patient tracking computer, thegraphical display presents predetermined distance and predeterminedduration in comparison to the calculated distance and the calculatedduration.
 10. The system of claim 1, wherein the algorithm applied bythe patient tracking computer is derived from analysis of historicalpatient location information.
 11. The system of claim 10, wherein thealgorithm is derived using an advanced neural network (ANN).
 12. Thesystem of claim 1 wherein the patient tracking computer calculates thedistance traveled by the patient as an average of distances of each ofthe plurality of possible paths weighted by the probability associatedwith each of the possible paths.
 13. The system of claim 1 wherein thepatient tracking computer calculates the distance traveled by thepatient at a distance of a selected path of the plurality of possiblepaths having a highest probability associated with the path.
 14. Thesystem of claim 1 wherein the patient tracking computer furthercalculates an average speed from the duration of patient ambulation andthe calculated distance traveled by the patient.
 15. The system of claim1 wherein the patient tracking computer further correlates thephysiological value to the duration of patient ambulation and thecalculated distance traveled by the patient.
 16. A system fortelemetrically monitoring a patient, the system comprising: a remotemonitoring device associated with the patient, the remote monitoringdevice obtains physiological values from the patient and broadcasts thephysiological values; a location service (LS) system that tracks aplurality of locations of the remote monitoring device; and a patienttracking computer connected to the remote monitoring device and the LSsystem, the patient tracking computer receives the physiological valuesand the tracked plurality of locations of the remote monitoring device,and executes computer readable code that causes the patient trackingcomputer to determine an ambulatory event with a start and an end withinthe received plurality of locations, calculate a distance traveled bythe patient during the ambulatory event, and calculate a duration forthe ambulatory event, wherein the patient tracking computer applies analgorithm that identifies a plurality of possible paths between a firstlocation of the plurality of locations and a second location of theplurality of locations of the remote monitoring device and calculates aprobability associated with each of the possible paths in calculatingthe distance traveled by the patient during the ambulatory event. 17.The system of claim 16 wherein the patient tracking computer receives aprescribed route and the patient tracking computer determines theambulatory event start and end based upon the prescribed route.
 18. Thesystem of claim 17, wherein the prescribed route comprises a pluralityof locations tracked by the LS system.
 19. The system of claim 18,wherein the patient tracking computer executes computer readable codethat causes the patient tracking computer to calculate at least onecorrelation between the physiological values and at least one of theambulatory event, distance traveled, and duration, and stores thecalculated at least one correlation in a patient electronic medicalrecord.
 20. The system of claim 16 wherein the patient tracking computercalculates the distance traveled by the patient during the ambulatoryevent as a distance of a selected path of the plurality of possiblepaths having a highest probability associated with the path.
 21. thesystem of claim 16 wherein the patient tracking computer calculates thedistance traveled by the patient during the ambulatory event as anaverage of distances of each of the plurality of possible paths weightedby the probability associated with each of the possible paths.
 22. Asystem for telemetrically monitoring a patient, the system comprising: aremote monitoring device associated with the patient, the remotemonitoring device obtains physiological values from the patient andbroadcasts the physiological values; a location service (LS) system thattracks a plurality of locations of the remote monitoring device; and apatient tracking computer connected to the remote monitoring device andthe LS system, the patient tracking computer receives the physiologicalvalues and the tracked plurality of locations of the remote monitoringdevice, and executes computer readable code that causes the patienttracking computer to determine an ambulatory event with an event startand an event end within the received tracked plurality of location, thepatient tracking computer identifies a plurality of possible pathsbetween a first location and a second location between the event startand the event end and identifies a probability associated with each ofthe plurality of possible paths, the patient tracking computercalculates a distance traveled by the patient during the ambulatoryevent in part based upon a distance of each of the identified possiblepaths and probabilities associated with possible paths, and calculates aduration for the ambulatory event between the determined event start andevent end.
 23. The system of claim 22 where the plurality of possiblepaths and probability associated with each of the plurality of possiblepaths are identified from historical patient ambulation data, andwherein the patient tracking computer calculates a distance between thefirst location and the second location within the ambulatory event byselecting a distance of a path of the plurality of paths associated witha highest probability.